Loud idle

2003 MERCEDES BENZ C320
239,616 MILES • 3.2L • V6 • 4WD • AUTOMATIC
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BLACKNACOUSTIC
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Hey I bought a this car secondhand from someone and have been working on it. I have replaced the filters (air,oil, transmission) and put new ignition coils in as well. It's in limp mode currently and it idles very hard and makes a knocking like sound from the tappets cover or in the valve cover area making it sound like a diesel engine. Any suggestions or ideas?
Nov 18, 2019 at 2:51 PM
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JACOBANDNICKOLAS
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Hi,

First, is it possible for you to record and upload the sound so I can hear it? Also, have you checked oil pressure and scanned for diagnostic trouble codes?

Let me know.
Joe
Nov 19, 2019 at 7:42 PM
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BLACKNACOUSTIC
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Lol. so I will send a video tomorrow when i can get in front of the car. But i'm unable to scan because the scan tool turns on when plugged in but wont connect.
Nov 19, 2019 at 7:47 PM
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BLACKNACOUSTIC
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Here is the video of the noise.
Video (Click to enlarge)
Attached Media
Nov 20, 2019 at 12:11 PM
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JACOBANDNICKOLAS
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Hi,

I do hear a lifter noise. It can be caused by low oil pressure or a bad lifter. Is that what you are referring to?
Nov 20, 2019 at 3:17 PM
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BLACKNACOUSTIC
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Yes I believe so. I will have it checked out and keep you updated.
Nov 20, 2019 at 3:24 PM
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JACOBANDNICKOLAS
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Hi,

The ticking is a lifter. Let me know what you find or if you have other questions.

Take care,
Joe
Nov 20, 2019 at 4:17 PM